Washington (CNN) -- Brushing recent public spats aside, the Obama administration welcomed Hamid Karzai to Washington on Tuesday, opening a round of partnership talks with the Afghan president.
At a breakfast meeting, U.S. Secretary of State Hillary Clinton welcomed Karzai for several days of partnership talks. Later Tuesday, Clinton is expected to hold closed-door bilateral talks with Karzai. President Obama will host his Afghan counterpart at the White House on Wednesday.
Clinton said Tuesday that the United States' commitment to Afghanistan remains strong and will continue long after U.S. combat troops have withdrawn. But she said it was unrealistic to expect the two nations to see eye to eye on every issue.
"President Obama and President Karzai both understand that the ability to disagree on issues of importance is not an obstacle to achieving our shared objectives, but rather it reflects a level of trust," she said.
Karzai expressed thanks on behalf of the Afghan nation to the American people for the sacrifices they have made there. He said Afghanistan will remain a dependable partner with the United States and its allies in the global war on terrorism.
However, he also acknowledged the recent rift.
"As two mature nations and two mature governments -- by now the Afghan government is mature, too -- we will have disagreements time to time, but that is a sign of a mature relationship and a steady relationship."
Karzai's first visit to Washington after his re-election comes after prickly talk centering on the Afghan president's ability to rein in corruption and institute good governance practices.
He was handed a victory in last August's national vote, marred by irregularities that forced a runoff. Since then, the Obama administration has publicly pressured Karzai to rid his government of graft and improve delivery of services to the Afghan people.
House Majority Leader Steny Hoyer told reporters Tuesday that he isn't satisfied that Karzai is doing enough to root out corruption in Afghanistan. The issue is "of great concern" to American taxpayers, who are helping to pay the costs of stabilizing and securing Afghanistan, he said.
"President Karzai and others in Afghanistan have a responsibility and they have a need to ... eliminate corruption, which undermines the stability of their country [and] undermines their credibility with the Afghan people, and the evidence to date has not been as hopeful as we would like," said Hoyer, D-Maryland.
He said the House of Representatives will vote on a $33 billion supplemental spending bill to fund ongoing U.S. military and diplomatic operations in Afghanistan and Iraq before the Memorial Day break at the end of the month. But he said he will wait until the Senate acts on the legislation before scheduling a House vote.
Karzai irritated U.S. officials when he blamed election fraud on foreigners who want a "puppet government" in Afghanistan. He further aggravated his most powerful ally when he told tribal leaders that the U.S.-led military alliance would not move against Taliban fighters in Kandahar "until you say we can."
Media reports have also included harsh criticism of Karzai by a former United Nations diplomat as well as claims that Karzai said he would consider joining the Taliban insurgency.
At one point, the White House indicated it would call off this week's visit.
But in recent weeks, the United States and Afghanistan have sought to play down their differences, rejecting the idea of any dispute between its leaders.
U.S. Ambassador Karl Eikenberry said Monday that there have been "ups and downs" in the relationship with Karzai.
He said he expects the United States and Afghanistan "to be able to work our way through difficulties and come back together and still find ourselves well-aligned" as a result of Karzai's talks with Obama.
"There will be serious dialogues in the days ahead on far-ranging issues, including how to best deliver on our government's commitment to help accelerate the strengthening of Afghan security and judicial institutions," Eikenberry said.
Asked if Karzai is a dependable partner for the United States, Eikenberry responded that he is the elected president of a close friend and ally. At the same time, he said that Karzai's government must improve transparency and accountability, and that those issues will be discussed this week.
"The United States government, I know our administration, is in full support of President Karzai's efforts right now to make improvements there," Eikenberry said. "Much has to be done."
Karzai's visit also comes as questions arise about the timing of a planned U.S.-led military offensive on the Kandahar area that is the spiritual center of the Taliban.
U.S. military leaders acknowledged challenges to the eventual goal of turning over security to the Afghans.
"We will encounter increased violence as our combined security forces expand into Taliban-controlled areas," said Gen. Stanley McChrystal, the allied military leader.
McChrystal offered no specifics on when the offensive might start but said securing control of the region is a goal of the U.S. mission in Afghanistan.
"Our strategic priority is a development of the Afghan National Army and police, the forces that will ultimately secure Afghanistan," he said. "Much work lies ahead to mature this force, but its growth is largely on track."